Theemployeeswereaskedtoconcentratetheirattentionimprovingthequalityoftheproducts.A．inB．toC．with

Question

The employees were asked to concentrate their attention________improving the quality of the products.

A ． in                                                      B ． to   

C ． with                                                   D ． on

Answer 1

D 　 考查固定短语。 concentrate one ’ s attention on doing sth. 意为
“ 集中精力做某事 ” 。